1. Field of the Invention
The present invention relates to a leak detector for an intra-aortic balloon pump, which uses a fluid of helium gas or the like for inflating a balloon, and more particularly to a detector for detecting a leak of fluid such as helium gas from a balloon inflated by the fluid through an isolating device.
2. Description of the Prior Art
A conventional intra-aortic balloon pump apparatus is disclosed in U.S. Pat. No. 4,733,652, as illustrated in FIG. 3 of the present application, where reference numeral 50 indicates a balloon, 51 a catheter, and 52 a port for introducing helium gas into the balloon 50, respectively. The balloon 50 is adapted to be inflated and deflated by means of helium gas fed through the catheter 51, and is inserted into the patient, usually through the femoral artery either percutaneously or through a partial incision, and advanced until it lies within the thoracic aorta descendens. Then, the balloon 50 is inflated or deflated in synchronous relationship with the pulsation of the heart so as to reduce the load on the left ventricle and increase the amount of coronary blood flow.
In the conventional intra-aortic balloon pump as described above, helium gas is mainly used as the fluid for inflating the balloon, and the balloon is inflated and deflated by introducing and discharging the fluid. Therefore, if the fluid leaks out of the apparatus by some causes, the balloon will not be inflated or deflated sufficiently. Accordingly, a detector for detecting a leak of fluid from the balloon pump has been required for the intra-aortic balloon pump apparatus.
For detecting the fluid leak, a method for visually examining an isolating device of the intra-aortic balloon pump, a method for detecting an extraordinary mass of fluid discharged at the time of feeding the fluid, and the like method have been conventionally used.
However, it is difficult for a person to examine the fluid leak visually. As to the method for detecting the fluid leak by means of the discharged mass of fluid, a certain period of time is needed until the extraordinary mass of fluid is discharged, and it is difficult to establish a stationary monitoring system.